Java Tutorial/File/Delete
Содержание
- 1 Delete all files under this file and including this file
- 2 Deletes a directory.
- 3 Deletes all files and subdirectories
- 4 Deletes the diretory and any files and directories in it recursively.
- 5 Delete the file or non-empty directory at the supplied path
- 6 Empty and delete a folder (and subfolders).
- 7 Recursive directory deletion
- 8 Recursively delete a file and all its contents
- 9 Recursivly delete directory
- 10 Remove a directory and all of its contents.
- 11 Remove file or directory
Delete all files under this file and including this file
import java.io.File;
import java.io.IOException;
public class Utils {
/**
* delete all files under this file and including this file
*
* @param f
* @throws IOException
*/
public static void deleteAll(File f) throws IOException {
recurse(f, new RecurseAction() {
public void doFile(File file) throws IOException {
file.delete();
if (file.exists()) {
throw new IOException("Failed to delete " + file.getPath());
}
}
public void doBeforeFile(File f) {
}
public void doAfterFile(File f) {
}
});
}
public static void recurse(File f, RecurseAction action) throws IOException {
action.doBeforeFile(f);
if (f.isDirectory()) {
File[] files = f.listFiles();
if (files != null) {
for (int i = 0; i < files.length; i++) {
if (files[i].isDirectory()) {
recurse(files[i], action);
} else {
action.doFile(files[i]);
}
}
}
}
action.doFile(f);
}
}
interface RecurseAction {
/**
* @param file
* @throws IOException
*/
void doFile(File file) throws IOException;
/**
* @param f
*/
void doBeforeFile(File f);
/**
* @param f
*/
void doAfterFile(File f);
}
Deletes a directory.
import java.io.File;
import java.io.IOException;
public class Utils {
/**
* Deletes a directory.
*
* @param dir the file for the directory to delete
* @return true if susscess
*/
public static boolean deleteDir(File dir) {
if (dir.isDirectory()) {
for (File file : dir.listFiles()) {
if (file.isDirectory()) {
try {
if (file.getCanonicalFile().getParentFile().equals(dir.getCanonicalFile())) {
deleteDir(file);
if (file.exists() && !file.delete()) {
System.out.println("Can"t delete: " + file);
}
} else {
System.out.println("Warning: " + file + " may be a symlink. Ignoring.");
}
} catch (IOException e) {
System.out.println("Warning: Cannot determine canonical file for " + file + " - ignoring.");
}
} else {
if (file.exists() && !file.delete()) {
System.out.println("Can"t delete: " + file);
}
}
}
return dir.delete();
}
return false;
}
}
Deletes all files and subdirectories
/**
* Copyright (c) 2003 - 2007 OpenSubsystems s.r.o. Slovak Republic. All rights reserved.
*
* Project: OpenSubsystems
*
* $Id: FileUtils.java,v 1.12 2007/02/01 07:18:32 bastafidli Exp $
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Arrays;
import java.util.Date;
import java.util.List;
import java.util.Properties;
import java.util.logging.Logger;
/**
* Collection of methods to make work with files easier.
*
* @version $Id: FileUtils.java,v 1.12 2007/02/01 07:18:32 bastafidli Exp $
* @author Miro Halas
* @code.reviewer Miro Halas
* @code.reviewed 1.7 2006/05/21 03:45:37 bastafidli
*/
public class FileUtils
{
// Configuration settings ///////////////////////////////////////////////////
/**
* Default 10 digit file storage distribution array. This means that if I
* want to name file as 10 digit number e.g. number 123 as 0000000123 or
* number 123456789 as 01234567890. Then the path constructed from number
* 1234567890 using distribution 2/2/2/4 would be 12/34/56/0123456789
*/
public static final int[] DEFAULT_STRORAGE_TREE_DISTRIBUTION = {2, 2, 2, 4};
/**
* How big buffer to use to process files.
*/
public static final int BUFFER_SIZE = 65536;
// Cached values ////////////////////////////////////////////////////////////
/**
* Temporary directory to use. It is guarantee that it ends with \ (or /)
*/
protected static String s_strTempDirectory;
// Constructors /////////////////////////////////////////////////////////////
/**
* Move file to a new location. If the destination is on different volume,
* this file will be copied and then original file will be deleted.
* If the destination already exists, this method renames it with different
* name and leaves it in that directory and moves the new file along side
* the renamed one.
*
* @param flCurrent - file to move
* @param flDestination - destination file
* @throws IOException - error message
* @throws OSSException - error message
*/
public static void moveFile(
File flCurrent,
File flDestination
) throws IOException
{
// Make sure that the source exist, it might be already moved from
// a directory and we just don"t know about it
if (flCurrent.exists())
{
// Next check if the destination file exists
if (flDestination.exists())
{
// If the destination exists, that means something went wrong
// Rename the destination file under temporaty name and try to
// move the new file instead of it
renameToTemporaryName(flDestination, "old");
}
// Make sure the directory exists and if not create it
File flFolder;
flFolder = flDestination.getParentFile();
if ((flFolder != null) && (!flFolder.exists()))
{
if (!flFolder.mkdirs())
{
// Do not throw the exception if the directory already exists
// because it was created meanwhile for example by a different
// thread
if (!flFolder.exists())
{
throw new IOException("Cannot create directory " + flFolder);
}
}
}
// Now everything should exist so try to rename the file first
// After testing, this renames files even between volumes C to H
// so we don"t have to do anything else on Windows but we still
// have to handle erro on Unix
if (!flCurrent.renameTo(flDestination))
{
// Try to copy and delete since the rename doesn"t work on Solaris
// between file systems
copyFile(flCurrent, flDestination);
// Now delete the file
if (!flCurrent.delete())
{
// Delete the destination file first since we haven"t really moved
// the file
flDestination.delete();
throw new IOException("Cannot delete already copied file " + flCurrent);
}
}
}
}
/**
* Copy the current file to the destination file.
*
* @param flCurrent - source file
* @param flDestination - destination file
* @throws IOException - error message
* @throws OSSException - error message
*/
public static void copyFile(
File flCurrent,
File flDestination
) throws IOException
{
// Make sure the directory exists and if not create it
File flFolder;
flFolder = flDestination.getParentFile();
if ((flFolder != null) && (!flFolder.exists()))
{
if (!flFolder.mkdirs())
{
// Do not throw the exception if the directory already exists
// because it was created meanwhile for example by a different
// thread
if (!flFolder.exists())
{
throw new IOException("Cannot create directory " + flFolder);
}
}
}
// FileChannel srcChannel = null;
// FileChannel dstChannel = null;
FileInputStream finInput = null;
//MHALAS: This code is not working reliably on Solaris 8 with 1.4.1_01
// Getting exceptions from native code
/*
// Create channel on the source
srcChannel = new FileInputStream(flCurrent).getChannel();
// Create channel on the destination
dstChannel = new FileOutputStream(flDestination).getChannel();
// Copy file contents from source to destination
dstChannel.transferFrom(srcChannel, 0, srcChannel.size());
Don"t forget to close the channels if you enable this code again
*/
try
{
finInput = new FileInputStream(flCurrent);
}
catch (IOException ioExec)
{
if (finInput != null)
{
try
{
finInput.close();
}
catch (Throwable thr)
{
}
}
throw ioExec;
}
FileUtils.copyStreamToFile(finInput, flDestination);
}
/**
* Rename the file to temporaty name with given prefix
*
* @param flFileToRename - file to rename
* @param strPrefix - prefix to use
* @throws IOException - error message
*/
public static void renameToTemporaryName(
File flFileToRename,
String strPrefix
) throws IOException
{
assert strPrefix != null : "Prefix cannot be null.";
String strParent;
StringBuffer sbBuffer = new StringBuffer();
File flTemp;
int iIndex = 0;
strParent = flFileToRename.getParent();
// Generate new name for the file in a deterministic way
do
{
iIndex++;
sbBuffer.delete(0, sbBuffer.length());
if (strParent != null)
{
sbBuffer.append(strParent);
sbBuffer.append(File.separatorChar);
}
sbBuffer.append(strPrefix);
sbBuffer.append("_");
sbBuffer.append(iIndex);
sbBuffer.append("_");
sbBuffer.append(flFileToRename.getName());
flTemp = new File(sbBuffer.toString());
}
while (flTemp.exists());
// Now we should have unique name
if (!flFileToRename.renameTo(flTemp))
{
throw new IOException("Cannot rename " + flFileToRename.getAbsolutePath()
+ " to " + flTemp.getAbsolutePath());
}
}
/**
* Delete all files and directories in directory but do not delete the
* directory itself.
*
* @param strDir - string that specifies directory to delete
* @return boolean - sucess flag
*/
public static boolean deleteDirectoryContent(
String strDir
)
{
return ((strDir != null) && (strDir.length() > 0))
? deleteDirectoryContent(new File(strDir)) : false;
}
/**
* Delete all files and directories in directory but do not delete the
* directory itself.
*
* @param fDir - directory to delete
* @return boolean - sucess flag
*/
public static boolean deleteDirectoryContent(
File fDir
)
{
boolean bRetval = false;
if (fDir != null && fDir.isDirectory())
{
File[] files = fDir.listFiles();
if (files != null)
{
bRetval = true;
boolean dirDeleted;
for (int index = 0; index < files.length; index++)
{
if (files[index].isDirectory())
{
// TODO: Performance: Implement this as a queue where you add to
// the end and take from the beginning, it will be more efficient
// than the recursion
dirDeleted = deleteDirectoryContent(files[index]);
if (dirDeleted)
{
bRetval = bRetval && files[index].delete();
}
else
{
bRetval = false;
}
}
else
{
bRetval = bRetval && files[index].delete();
}
}
}
}
return bRetval;
}
/**
* Deletes all files and subdirectories under the specified directory including
* the specified directory
*
* @param strDir - string that specifies directory to be deleted
* @return boolean - true if directory was successfully deleted
*/
public static boolean deleteDir(
String strDir
)
{
return ((strDir != null) && (strDir.length() > 0))
? deleteDir(new File(strDir)) : false;
}
/**
* Deletes all files and subdirectories under the specified directory including
* the specified directory
*
* @param fDir - directory to be deleted
* @return boolean - true if directory was successfully deleted
*/
public static boolean deleteDir(
File fDir
)
{
boolean bRetval = false;
if (fDir != null && fDir.exists())
{
bRetval = deleteDirectoryContent(fDir);
if (bRetval)
{
bRetval = bRetval && fDir.delete();
}
}
return bRetval;
}
/**
* Compare binary files. Both files must be files (not directories) and exist.
*
* @param first - first file
* @param second - second file
* @return boolean - true if files are binery equal
* @throws IOException - error in function
*/
public boolean isFileBinaryEqual(
File first,
File second
) throws IOException
{
// TODO: Test: Missing test
boolean retval = false;
if ((first.exists()) && (second.exists())
&& (first.isFile()) && (second.isFile()))
{
if (first.getCanonicalPath().equals(second.getCanonicalPath()))
{
retval = true;
}
else
{
FileInputStream firstInput = null;
FileInputStream secondInput = null;
BufferedInputStream bufFirstInput = null;
BufferedInputStream bufSecondInput = null;
try
{
firstInput = new FileInputStream(first);
secondInput = new FileInputStream(second);
bufFirstInput = new BufferedInputStream(firstInput, BUFFER_SIZE);
bufSecondInput = new BufferedInputStream(secondInput, BUFFER_SIZE);
int firstByte;
int secondByte;
while (true)
{
firstByte = bufFirstInput.read();
secondByte = bufSecondInput.read();
if (firstByte != secondByte)
{
break;
}
if ((firstByte < 0) && (secondByte < 0))
{
retval = true;
break;
}
}
}
finally
{
try
{
if (bufFirstInput != null)
{
bufFirstInput.close();
}
}
finally
{
if (bufSecondInput != null)
{
bufSecondInput.close();
}
}
}
}
}
return retval;
}
/**
* Get path which represents temporary directory. It is guarantee that it
* ends with \ (or /).
*
* @return String
*/
public static String getTemporaryDirectory(
)
{
return s_strTempDirectory;
}
/**
* Copy any input stream to output file. Once the data will be copied
* the stream will be closed.
*
* @param input - InputStream to copy from
* @param output - File to copy to
* @throws IOException - error in function
* @throws OSSMultiException - double error in function
*/
public static void copyStreamToFile(
InputStream input,
File output
) throws IOException
{
FileOutputStream foutOutput = null;
// open input file as stream safe - it can throw some IOException
try
{
foutOutput = new FileOutputStream(output);
}
catch (IOException ioExec)
{
if (foutOutput != null)
{
try
{
foutOutput.close();
}
catch (IOException ioExec2)
{
}
}
throw ioExec;
}
// all streams including os are closed in copyStreamToStream function
// in any case
copyStreamToStream(input, foutOutput);
}
/**
* Copy any input stream to output stream. Once the data will be copied
* both streams will be closed.
*
* @param input - InputStream to copy from
* @param output - OutputStream to copy to
* @throws IOException - io error in function
* @throws OSSMultiException - double error in function
*/
public static void copyStreamToStream(
InputStream input,
OutputStream output
) throws IOException
{
InputStream is = null;
OutputStream os = null;
int ch;
try
{
if (input instanceof BufferedInputStream)
{
is = input;
}
else
{
is = new BufferedInputStream(input);
}
if (output instanceof BufferedOutputStream)
{
os = output;
}
else
{
os = new BufferedOutputStream(output);
}
while ((ch = is.read()) != -1)
{
os.write(ch);
}
os.flush();
}
finally
{
IOException exec1 = null;
IOException exec2 = null;
try
{
// because this close can throw exception we do next close in
// finally statement
if (os != null)
{
try
{
os.close();
}
catch (IOException exec)
{
exec1 = exec;
}
}
}
finally
{
if (is != null)
{
try
{
is.close();
}
catch (IOException exec)
{
exec2 = exec;
}
}
}
if ((exec1 != null) && (exec2 != null))
{
throw exec1;
}
else if (exec1 != null)
{
throw exec1;
}
else if (exec2 != null)
{
throw exec2;
}
}
}
}
Deletes the diretory and any files and directories in it recursively.
/*
* Copyright Aduna (http://www.aduna-software.ru/) (c) 1997-2006.
*
* Licensed under the Aduna BSD-style license.
*/
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
public class Main {
/**
* Deletes the specified diretory and any files and directories in it
* recursively.
*
* @param dir The directory to remove.
* @throws IOException If the directory could not be removed.
*/
public static void deleteDir(File dir)
throws IOException
{
if (!dir.isDirectory()) {
throw new IOException("Not a directory " + dir);
}
File[] files = dir.listFiles();
for (int i = 0; i < files.length; i++) {
File file = files[i];
if (file.isDirectory()) {
deleteDir(file);
}
else {
boolean deleted = file.delete();
if (!deleted) {
throw new IOException("Unable to delete file" + file);
}
}
}
dir.delete();
}
}
Delete the file or non-empty directory at the supplied path
/*
* JBoss DNA (http://www.jboss.org/dna)
* See the COPYRIGHT.txt file distributed with this work for information
* regarding copyright ownership. Some portions may be licensed
* to Red Hat, Inc. under one or more contributor license agreements.
* See the AUTHORS.txt file in the distribution for a full listing of
* individual contributors.
*
* JBoss DNA is free software. Unless otherwise indicated, all code in JBoss DNA
* is licensed to you under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* JBoss DNA is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
import java.io.File;
public class FileMonitor {
/**
* Delete the file or directory at the supplied path. This method works on a directory that is not empty, unlike the
* {@link File#delete()} method.
*
* @param path the path to the file or directory that is to be deleted
* @return true if the file or directory at the supplied path existed and was successfully deleted, or false otherwise
*/
public static boolean delete( String path ) {
if (path == null || path.trim().length() == 0) return false;
return delete(new File(path));
}
/**
* Delete the file or directory given by the supplied reference. This method works on a directory that is not empty, unlike
* the {@link File#delete()} method.
*
* @param fileOrDirectory the reference to the Java File object that is to be deleted
* @return true if the supplied file or directory existed and was successfully deleted, or false otherwise
*/
public static boolean delete( File fileOrDirectory ) {
if (fileOrDirectory == null) return false;
if (!fileOrDirectory.exists()) return false;
// The file/directory exists, so if a directory delete all of the contents ...
if (fileOrDirectory.isDirectory()) {
for (File childFile : fileOrDirectory.listFiles()) {
delete(childFile); // recursive call (good enough for now until we need something better)
}
// Now an empty directory ...
}
// Whether this is a file or empty directory, just delete it ...
return fileOrDirectory.delete();
}
}
Empty and delete a folder (and subfolders).
import java.io.File;
public class Utils {
/**
* Empty and delete a folder (and subfolders).
* @param folder
* folder to empty
*/
public static void rmdir(final File folder) {
// check if folder file is a real folder
if (folder.isDirectory()) {
File[] list = folder.listFiles();
if (list != null) {
for (int i = 0; i < list.length; i++) {
File tmpF = list[i];
if (tmpF.isDirectory()) {
rmdir(tmpF);
}
tmpF.delete();
}
}
if (!folder.delete()) {
System.out.println("can"t delete folder : " + folder);
}
}
}
}
Recursive directory deletion
/**
*
* The ObjectStyle Group Software License, version 1.1
* ObjectStyle Group - http://objectstyle.org/
*
* Copyright (c) 2002-2005, Andrei (Andrus) Adamchik and individual authors
* of the software. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution, if any,
* must include the following acknowlegement:
* "This product includes software developed by independent contributors
* and hosted on ObjectStyle Group web site (http://objectstyle.org/)."
* Alternately, this acknowlegement may appear in the software itself,
* if and wherever such third-party acknowlegements normally appear.
*
* 4. The names "ObjectStyle Group" and "Cayenne" must not be used to endorse
* or promote products derived from this software without prior written
* permission. For written permission, email
* "andrus at objectstyle dot org".
*
* 5. Products derived from this software may not be called "ObjectStyle"
* or "Cayenne", nor may "ObjectStyle" or "Cayenne" appear in their
* names without prior written permission.
*
* THIS SOFTWARE IS PROVIDED ``AS IS"" AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE OBJECTSTYLE GROUP OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*
* This software consists of voluntary contributions made by many
* individuals and hosted on ObjectStyle Group web site. For more
* information on the ObjectStyle Group, please see
* <http://objectstyle.org/>.
*/
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.OutputStream;
import java.io.Serializable;
import java.lang.reflect.Member;
import java.lang.reflect.Modifier;
import java.net.URL;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.ruparator;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.regex.Pattern;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
/**
* Contains various unorganized static utility methods used across Cayenne.
*
* @author Andrei Adamchik
*/
public class Util {
/**
* Deletes a file or directory, allowing recursive directory deletion. This is an
* improved version of File.delete() method.
*/
public static boolean delete(String filePath, boolean recursive) {
File file = new File(filePath);
if (!file.exists()) {
return true;
}
if (!recursive || !file.isDirectory())
return file.delete();
String[] list = file.list();
for (int i = 0; i < list.length; i++) {
if (!delete(filePath + File.separator + list[i], true))
return false;
}
return file.delete();
}
}
Recursively delete a file and all its contents
import java.io.File;
public class Utils {
/**
* Recursively delete a file and all its contents.
*
* @param root
* the root to delete
*/
public static void recursiveDelete(File root) {
if (root == null) {
return;
}
if (root.isDirectory()) {
File[] files = root.listFiles();
if (files != null) {
for (int i = 0; i < files.length; i++) {
File file = files[i];
if (file.isDirectory()) {
recursiveDelete(file);
} else {
file.delete();
}
}
}
}
root.delete();
}
}
Recursivly delete directory
import java.io.File;
public class DirectoryIO {
/**
*
* recursivly delete directory
*
* @param directory
*/
public static boolean delete(File directory) {
boolean result = false;
if (directory.isDirectory()) {
File[] files = directory.listFiles();
for (int i = 0; i < files.length; i++) {
if (files[i].isDirectory()) {
delete(files[i]);
}
files[i].delete();
}
result = directory.delete();
}
return result;
}
}
Remove a directory and all of its contents.
import java.io.File;
import java.util.StringTokenizer;
/*
Derby - Class org.apache.derby.iapi.util.PropertyUtil
Licensed to the Apache Software Foundation (ASF) under one or more
contributor license agreements. See the NOTICE file distributed with
this work for additional information regarding copyright ownership.
The ASF licenses this file to you under the Apache License, Version 2.0
(the "License"); you may not use this file except in compliance with
the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
public class Main {
/**
Remove a directory and all of its contents.
The results of executing File.delete() on a File object
that represents a directory seems to be platform
dependent. This method removes the directory
and all of its contents.
@return true if the complete directory was removed, false if it could not be.
If false is returned then some of the files in the directory may have been removed.
*/
public static boolean removeDirectory(File directory) {
// System.out.println("removeDirectory " + directory);
if (directory == null)
return false;
if (!directory.exists())
return true;
if (!directory.isDirectory())
return false;
String[] list = directory.list();
// Some JVMs return null for File.list() when the
// directory is empty.
if (list != null) {
for (int i = 0; i < list.length; i++) {
File entry = new File(directory, list[i]);
// System.out.println("\tremoving entry " + entry);
if (entry.isDirectory())
{
if (!removeDirectory(entry))
return false;
}
else
{
if (!entry.delete())
return false;
}
}
}
return directory.delete();
}
}
Remove file or directory
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*
*/
import java.io.File;
import java.io.FileFilter;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
/**
*
* FileUtils is a collection of routines for common file system operations.
*
* @author Dan Jemiolo (danj)
*
*/
public final class FileUtils {
/**
*
* Starts at the directory given and tests to see whether it is empty; if so,
* it deletes it and moves up the directory tree, deleting empty directories
* until it finds a non-empty one.
*
* @param directory
* The first directory to test.
*
* @throws IOException
* <ul>
* <li>If the directory does not exist or the user does not have
* permission to delete it or its parents.</li>
* </ul>
*
*/
public static void pruneEmptyDirectories(File directory) throws IOException {
if (directory == null)
throw new NullPointerException("NullFile");
if (!directory.isDirectory()) {
Object[] filler = { directory.getAbsolutePath() };
String message = "NotDirectory";
throw new IllegalArgumentException(message);
}
//
// check to see if the directory is now empty and, if so, delete it
// too, moving up the tree until we find one with stuff in it
//
while (directory != null) {
File[] directoryFiles = directory.listFiles();
//
// if the directory has files, we"re done
//
if (directoryFiles.length > 0)
break;
if (!directory.delete()) {
Object[] filler = { directory.getAbsolutePath() };
String message = "DeleteFailed";
throw new IOException(message);
}
//
// go up the tree
//
directory = directory.getParentFile();
}
}
/**
*
* The application"s current working directory.
*
*/
public static final File CURRENT_DIR = new File(".");
/**
*
* This is a convenience method that calls remove(File, boolean) with the
* second parameter set to "false" (doesn"t prune empty directories).
*
* @see #remove(File, boolean)
*
*/
public static void remove(File file) throws IOException {
remove(file, false);
}
/**
*
* @param file
* The file or directory to delete.
*
* @param pruneEmptyDirectories
* True if the deletion results in an empty parent directory. If set
* to true, this method will traverse up the directory tree, deleting
* directories that are made empty by the deletion.
*
* @throws IOException
* <ul>
* <li>If there was an error trying to remove the file or
* directory. The file system may be in an inconsistent state when
* the exception is thrown (directories may be partially deleted,
* etc.).</li>
* </ul>
*
*/
public static void remove(File file, boolean pruneEmptyDirectories) throws IOException {
if (file == null)
throw new NullPointerException("NullFile");
if (file.isDirectory())
removeDirectory(file);
else
removeFile(file);
if (pruneEmptyDirectories)
pruneEmptyDirectories(file.getParentFile());
}
private static void removeDirectory(File directory) throws IOException {
File[] files = directory.listFiles();
//
// for all items in the directory...
//
for (int n = 0; n < files.length; ++n) {
File nextFile = files[n];
//
// if it"s a directory, delete sub-directories and files before
// removing the empty directory
//
if (nextFile.isDirectory())
removeDirectory(nextFile);
//
// otherwise just delete the file - do NOT prune the directory
// in advance
//
else
removeFile(nextFile);
}
//
// now that everything"s gone, delete the specified directory
//
if (!directory.delete()) {
Object[] filler = { directory.getAbsolutePath() };
String message = "DeleteFailed";
throw new IOException(message);
}
}
private static void removeFile(File file) throws IOException {
//
// make sure the file exists, then delete it
//
if (!file.exists())
throw new FileNotFoundException(file.getAbsolutePath());
if (!file.delete()) {
Object[] filler = { file.getAbsolutePath() };
String message = "DeleteFailed";
throw new IOException(message);
}
}
}
